TY - CONF A1 - Donsky, I. S. A1 - Lippitz, Andreas A1 - Adeli, M. A1 - Haag, R. A1 - Unger, Wolfgang T1 - 2D nanomaterials with switchable pathogen binding N2 - Graphene derivatives have shown great promise in the field of pathogen binding and sensing. Due to their diverse applications, they show a variety of activities that range from bacterial adhesion to bacterial resistance. Therefore, domination of the graphene-pathogen interactions is highly relevant for producing 2D platforms with the desired applications. In order to gain control over the interactions between graphene and biosystems, mechanisms should be fully understood. The surface functionality of graphene is one of the most important factors that dominates its interactions with biosystems and pathogens. Covalent functionalization is a robust method through which functionality, chemical structure, and subsequently physicochemical properties of graphene are abundantly manipulated. A critical issue for preparing graphene-based 2D materials with a defined surface structure, however, is controlling the functionalization in terms of number, position, and type of functional groups. T2 - 9th Joint BER II and BESSY II User Meeting CY - Berlin, Germany DA - 13.12.2017 KW - Graphene KW - Functionalization KW - XPS KW - C Kedge NEXAFS PY - 2017 AN - OPUS4-43456 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kok, H. T. A1 - Donskyi, Ievgen A1 - Adeli, M. A1 - Unger, Wolfgang A1 - Haag, R. T1 - 2D nanomaterials with switchable pathogen binding N2 - Graphene and its derivatives have recently attracted much attention for sensing and deactivating pathogens. However, mechanism of multivalent interactions at the graphene-pathogen interface are not fully understood. Since different physicochemical parameters of graphene play a role at this interface, control over graphene’s structure is necessary to study the mechanism of these interactions. In this work, zwitterionic graphene nanomaterials (ZGNMs) were synthesized with defined isoelectric points and exposure, in terms of polymer coverage and functionality. Then, the switchable interactions of ZGNMs with E. coli were investigated to study the validity of the generally proposed “trapping” mechanism for inactivating pathogens by functionalized graphene derivatives. The ZGNMs were able to controllably trap and release E. coli by crossing their isoelectric points. T2 - 4th Erlangen Symposium on Synthetic Carbon Allortopes 2017 CY - Erlangen, Germany DA - 25.09.2017 KW - Graphene KW - XPS KW - NEXAFS KW - Zwitterionic graphene nanomaterials PY - 2017 AN - OPUS4-47084 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Marzok, Ulrich A1 - Müller, Ralf A1 - Reetz, R. A1 - Lauven, G. T1 - 3D High-temperature laser profilometry during sintering N2 - Most crucial for components of complex shape or heterogeneous micro structure, precise control of sintering has decisive influence on dimensional accuracy, mechanical integrity and reliability of sintered components. In these cases, only in situ 3D high-temperature shape screening during shrinkage would allow revealing temporary sinter warpage and hereby caused potential defects. Against this background, nokra Optische Prüftechnik und Automation GmbH, HTM Reetz GmbH and BAM developed a testing device for in situ 3D shape screening for ceramic and glass-ceramic tapes up to 1000°C by means of high-temperature laser profilometry. The local repeatability of the sample-sensor distance (sample height profile) is 10 µm at 1000°C. Current work is focused on dropping these restrictions in sample shape and temperature. In a second testing device, currently being in development, samples up to 5 cm x 5 cm x 5 cm can be measured at temperatures up to 1500°C.The presentation illustrates the current state of this work and possible applications of the method. T2 - 92. DKG Jahrestagung CY - Berlin, Germany DA - 19. 03. 2017 KW - Laser profilometry KW - 3D High-temperatue shape screening KW - Sintering PY - 2017 AN - OPUS4-40449 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Patrick P. A1 - Hüllmann, Dino A1 - Detlefsen, Malte A1 - Kohlhoff, Harald T1 - A low-cost cable-suspended parallel manipulator for testing 3D olfaction algorithms N2 - Cable-suspended parallel manipulators have been a topic of research for multiple decades and called special attention in the fields of simulations. However, they are also well-suited for the simple evaluation of aerial-based mobile robot olfaction (MRO) algorithms, such as gas source localization and gas distribution mapping. Based on an open source framework for 3D printers, we designed a low-cost underconstrained, cable-suspended parallel manipulator. Computations are carried out purely on an Atmel ATmega2560 microcontroller. T2 - 33rd Danubia- Adria Symposium on Advances in Experimental Mechanics CY - Trieste, Italy DA - 19.09.2017 KW - Cable-suspended parallel manipulator KW - 3D KW - Mobile robot olfaction PY - 2017 AN - OPUS4-42317 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tvrdoňová, M. A1 - Ascher, Lena A1 - Jakubowski, Norbert A1 - Vaculovičová, M. A1 - Moravanská, A. A1 - Vaněčková, T. A1 - Vaculovič, T. T1 - A new strategy of reagents labeling (NPs) used in immunoassay with LA-ICP-MS N2 - Laser ablation with inductively coupled plasma is still more used in life science as biology and biomedicine and the utilization of metals and proteins determination simultaneously is also growing up. We have developed a new strategy of labeling of antibody (it can specific binds to proteins) by nanoparticles and quantum dots which is composed of thousands of atoms and thus increases the sensitivity enormously and of course decreases the Limit of detection, compare to lanthanoids labeling. The ability of successfully tagged antibodies bound to Antigen (protein) was proved by dot blot on membrane imaged by LA-ICP-MS. T2 - Euroanalysis 2017 CY - Stockholm, Sweden DA - 28.08.2017 KW - Immunoassay KW - LA-ICP-MS KW - Labeling KW - Nanoparticle PY - 2017 AN - OPUS4-43168 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reuther, R. A1 - Marvin, H. A1 - Müller, P. A1 - Löschner, K. A1 - Hodoroaba, Vasile-Dan A1 - Stintz, M. A1 - Kammer, F. v. d. A1 - Köber, R. A1 - Rauscher, H. T1 - A new tiered analytical approach and e-Tool for material classification to support the implementation of the EU Nano-Definition N2 - The EC recommendation for the definition of nanomaterial [2011/696/EU] requires the quantitative size determination of constituent particles in samples down to 1 nm. Accordingly, a material is a nanomaterial if 50 % or more of the particles are in the size range 1-100 nm. The fact that engineered nanomaterials already exist in many industrial and consumer products challenges the development of measurement methods to reliably identify, characterize and quantify their occurrence as substance and in various matrices. The EU FP7 NanoDefine project [www.nanodefine.eu] has addressed this challenge by developing a robust, readily implementable and cost-effective measurement strategy to obtain quantitative particle size distributions and to distinguish between nano and non-nano materials according to the EU definition. Based on a comprehensive evaluation of existing methodologies and intra- and inter-lab comparisons, validated measurement methods and instrument calibration procedures have been established to reliably measure the size of particles within 1-100 nm, and beyond, including different shapes, coatings and chemical compositions in industrial materials and consumer products. Case studies prove their applicability for various sectors, including food, pigments and cosmetics. Main outcome is the establishment of an integrated tiered approach including rapid screening (tier 1) and confirmatory methods (tier 2), and a user manual to guide end-users, such as manufacturers, in selecting appropriate methods. Another main product is the “NanoDefiner” e-Tool allowing the standardised / semi-automated selection of appropriate methods for material classification according to the EU definition. Results also contribute to standardization efforts, such as CEN TC 352 or ISO TC 229. T2 - EuroNanoForum 2017 CY - Valletta, Malta DA - 21.06.2017 KW - Nanomaterial classification KW - Nanoparticles KW - EC definition of nanomaterial KW - Tiered approach PY - 2017 UR - http://euronanoforum2017.eu/ AN - OPUS4-43993 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ramirez Caro, Alejandra A1 - Mota, Berta A1 - Artemeva, Elena A1 - Pauli, Jutta A1 - Schmidt, Wolfram A1 - Resch-Genger, Ute T1 - A spectroscopic study of the superplasticizer effect on early cement hydration N2 - Besides their plasticizing effect, superplasticizers (SPs) are known to retard the hydration of inorganic systems such as cement. Despite their frequent use, the understanding of these highly complex systems is still limited and the relevant parameters, which control the interaction between SPs, and cement components and reaction products are in the focus of ongoing research activities.[1] Optical methods have been successfully used for the analysis and monitoring of the interactions between a broad variety of nanoscale and molecular systems like nanoparticles of various chemical composition and different types of organic ligands or biomolecules. The potential of these methods to study processes at the interface between (hydrated) particles and the fluid phase at a very early stage of concrete formation could reveal possible mechanisms of interaction. This investigation focuses on the study of organic/inorganic mixtures consisting of cement (CEM) and cement phases (C3S and C3A) in the presence of polycarboxylate ether and organic dyes in aqueous solution (particularly alkali resistant dyes) at a water to powder ratio of 1. Diffuse reflectance as well as steady state and time resolved fluorescence spectroscopy of the above mentioned mixtures were evaluated. Based upon changes of the intensity of the reflectance and fluorescence signal and spectral changes of the dye, acting as optical reporter, a model for the interactions of dye, PCE and cement (including different cement phases) was derived which describes the very first stage of cement hydration. T2 - 2nd International Conference on Polycarboxylate Superplasticizers CY - München, Germany DA - 27.09.2017 KW - Cement KW - Superplasticizers KW - Dyes KW - Spectroscopy PY - 2017 AN - OPUS4-43365 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Carl, Peter A1 - Schneider, Rudolf A1 - Sarma, Dominik A1 - Rurack, Knut T1 - A wash-free, multiplex microbead assay for determination of emerging bioactive compounds in wastewater N2 - Pollutants of low molecular weight, such as drug residues, are in the focus of water quality assessment: some of them, like carbamazepine are only partially degraded in wastewater treatment plants. Thus, these pollutants can serve as marker substances for elimination efficiencies. Monitoring water quality demands for selective, high-throughput and multi-target analytical methods. Immunoassays, such as ELISA, offer the possibility to be highly sensitive and selective due to the specific recognition by high affinity of target molecules to antibodies (Abs). Batch-wise processing in microtiter plates allows for the necessary high-throughput, however only a single analyte can be determined within one measurement. To overcome these disadvantages, we developed a four-plex microbead-based flow cytometric assay, which is adaptable for the microtiter plate format. The modular and self-prepared bead support consists of polystyrene-core/silica-shell particles. While, the polystyrene core is used for encoding, by introducing different amounts of fluorescent dyes, the silica shell creates a solid support for the immunoassay: The target analytes, three drugs, carbamazepine, diclofenac and caffeine and the fecal marker isolithocholic acid are coupled covalently to the surface via NHS chemistry to amino groups on the surface. For determination of the pollutants, a mixture of specific Abs is incubated with the samples, to bind competitively on the “anchor” molecules on the surface of the beads or the analyte in solution. Bound antibodies are then visualized via fluorescent dye-labelled secondary Abs. Flow-cytometry allows for decoding of the beads and signal read-out, without washing the system. In order to decrease non-specific binding, we investigated different types of surface modifications, finding, that a PEG-based surface is suitable to support our immunoassay format. For maximum sensitivity, a design-of-experiment approach was chosen for optimization of the assay parameters. The resulting immunoassay is appropriate to quantify the pollutants in the low μg/L-range. T2 - EBS 2017 CY - Potsdam, Germany DA - 20.03.2017 KW - Immunoassay KW - Bead-based assay KW - Flow-cytometry PY - 2017 AN - OPUS4-39522 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Johann, Sergej A1 - Bartholmai, Matthias A1 - Neumann, Patrick P. A1 - Tiebe, Carlo A1 - Gawlitza, Kornelia A1 - Bartelmeß, Jürgen T1 - Adaptable multi-sensor device for gas detection N2 - Innovation is the catalyst for the technology of the future. It is important to develop new and better technologies that can continuously monitor the environmental impact, e.g., for air quality control or emission detection. In the recently at BAM developed Universal Pump Sensor Control (UPSC3) module, different components and sensors are fused. The combination of the individual components makes the UPSC3 module an excellent monitoring and reference system for the development and characterization of gas specific sensors. Measurements over long periods are possible, for mixed gas loads or for certain gas measurements. The system is part of a mobile sensor network of several sensor units, which can also be used as standalone systems. The motivation and objective of this research is to develop gas sensors based on fluorescence detection with range of ppm / ppb. For this task a reference system is required, which contains volatile organic compound (VOC) sensors for reference data from different scenarios. The integrated multi-sensor unit can measure different gases through the integrated 3-fold VOC sensor, which can be adapted to the addressed scenario. . The system-integrated flow control, with pump and flow sensor, allows the gas molecules to be transported directly to the VOC sensor. The entire measurement is permanently stored on an integrated memory card. If the previously determined limit range is exceeded, an alarm is generated. The system is an important tool towards further developments in the field of gas sensors and is primarily used for the validation of chemically based gas sensors. T2 - Colloquium of Optical Spectrometry (COSP) 2017 CY - Berlin, Germany DA - 27.11.2017 KW - Gas detection KW - Multi sensor device KW - Pump control KW - VOC PY - 2017 AN - OPUS4-43193 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bartholmai, Matthias A1 - Johann, Sergej A1 - Wu, Cheng-Chieh A1 - Neumann, Patrick P. A1 - Hüllmann, Dino A1 - Krentel, Daniel A1 - Kluge, Martin A1 - Kohlhoff, Harald A1 - Lilienthal, A.J. T1 - Airborne remote gas sensing and mapping N2 - Leaking methane (CH4) from infrastructures, such as pipelines and landfills, is critical for the environment but can also pose a safety risk. To enable a fast detection and localization of these kind of leaks, we developed a novel robotic platform for aerial remote gas sensing. Spectroscopic measurement methods for remote sensing of selected gases lend themselves for use on mini-copters, which offer a number of advantages for inspection and surveillance over traditional methods. No direct contact with the target gas is needed and thus the influence of the aerial platform on the measured gas plume can be kept to a minimum. This allows to overcome one of the major issues with gas-sensitive mini-copters. On the other hand, remote gas sensors, most prominently Tunable Diode Laser Absorption Spectroscopy (TDLAS) sensors have been too bulky given the payload and energy restrictions of mini-copters. Here, we present the Unmanned Aerial Vehicle for Remote Gas Sensing (UAV-REGAS), which combines a novel lightweight TDLAS sensor with a 3-axis aerial stabilization gimbal for aiming on a versatile hexacopter. The proposed system can be deployed in scenarios that cannot be addressed by currently available robots and thus constitutes a significant step forward for the field of Mobile Robot Olfaction (MRO). It enables tomographic reconstruction of gas plumes and a localization of gas sources. We also present first results showing its performance under realistic conditions. T2 - 5th International Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures (SMAR 2019) CY - Potsdam, Germany DA - 27.08.2019 KW - Localization of gas sources KW - Mobile Robot Olfaction KW - Tomographic reconstruction of gas plumes KW - Tunable Diode Laser Absorption Spectroscopy (TDLAS) KW - UAV-REGAS PY - 2017 AN - OPUS4-48789 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -